TBST Buffer Recipe (1X Tris-Buffered Saline with Tween 20)
TBST, also written TBS-T or TTBS, is Tris-buffered saline (TBS) containing the nonionic detergent Tween 20. It is commonly used as a wash buffer for Western blots and ELISAs, where Tween 20 helps reduce nonspecific binding.
1X TBST composition
This recipe makes 1X TBST containing 50 mM Tris·HCl, pH 7.4, 150 mM NaCl, and 0.1% Tween 20.
Prepare 1 L of 1X TBST
Use a prepared 10X TBS stock to make the working solution:
- 890 ml ultrapure water
- 100 ml 10X TBS
- 10 ml 10% Tween 20
- Add 890 ml of ultrapure water to a clean beaker and begin stirring.
- Add the 10X TBS stock slowly while continuing to stir.
- Add the 10% Tween 20 stock and mix until the solution is uniform.
Note: Tween 20 is viscous. A 10% stock is easier to measure accurately than neat Tween 20. Mix thoroughly after adding the detergent.
How TBST differs from TBS and PBST
TBS contains Tris and sodium chloride but no detergent. TBST is TBS supplemented with Tween 20. PBST is phosphate-buffered saline supplemented with Tween 20. Use the buffer specified by a validated protocol, antibody datasheet, or assay kit rather than substituting them automatically.
Use and handling notes
- For Western blotting, TBST is commonly used to wash membranes between blocking and antibody-incubation steps.
- For ELISA, TBST can be used for plate washes when it is compatible with the assay protocol.
- Tween 20 concentration, wash duration, temperature, and agitation affect wash stringency. Follow the conditions specified for the assay.
- Prepare fresh working buffer when required by the protocol. Discard solution that becomes visibly cloudy or contaminated.